webrtc: fix propagating query parameters when appending slash to paths (#2771)

internal/core/webrtc_http_server.go

@@ -352,7 +352,11 @@ func (s *webRTCHTTPServer) onRequest(ctx *gin.Context) {
 				s.onPage(ctx, ctx.Request.URL.Path[1:len(ctx.Request.URL.Path)-len("/publish")], true)
 
 			case ctx.Request.URL.Path[len(ctx.Request.URL.Path)-1] != '/':
-				ctx.Writer.Header().Set("Location", ctx.Request.URL.Path[1:]+"/")
+				l := ctx.Request.URL.Path[1:] + "/"
+				if ctx.Request.URL.RawQuery != "" {
+					l += "?" + ctx.Request.URL.RawQuery
+				}
+				ctx.Writer.Header().Set("Location", l)
 				ctx.Writer.WriteHeader(http.StatusMovedPermanently)
 
 			default: